PT  - JOURNAL ARTICLE
AU  - Schmitt, Volker H.
AU  - Schmitt, Christine
AU  - Hollemann, David
AU  - Mamilos, Andreas
AU  - Wagner, Willi
AU  - Weinheimer, Oliver
AU  - Brochhausen, Christoph
TI  - Comparison of histological and computed tomographic measurements of pig lung bronchi
AID  - 10.1183/23120541.00500-2020
DP  - 2020 Oct 01
TA  - ERJ Open Research
PG  - 00500-2020
VI  - 6
IP  - 4
4099  - http://openres.ersjournals.com/content/6/4/00500-2020.short
4100  - http://openres.ersjournals.com/content/6/4/00500-2020.full
SO  - erjor2020 Oct 01; 6
AB  - Aim Light microscopy is used as template in the evaluation and further development of medical imaging methods. Tissue shrinkage caused by histological processing is known to influence lung tissue dimensions. In diagnosis of COPD, computed tomography (CT) is widely used for automated airway measurement. The aim of this study was to compare histological and computed tomographic measurements of pig lung bronchi.Methods Airway measurements of pig lungs were performed after freezing under controlled inflation pressure in a liquid nitrogen bath. The wall thickness of seven bronchi was measured via Micro-CT and CT using the integral-based method (IBM) and the full-width-at-half-maximum method (FWHM) automatically and histologically on frozen and paraffin sections. Statistical analysis was performed using the Wilcoxon test, Pearson's correlation coefficient with a significance level at p<0.05, scatter plots and Bland–Altman plots.Results Bronchial wall thickness was smallest in frozen sections (median 0.71 mm) followed by paraffin sections (median 0.75 mm), Micro-CT (median 0.84 mm), and CT measurements using IBM (median 0.68 mm) and FWHM (median 1.69 mm). Statistically significant differences were found among all tested groups (p<0.05) except for CT IBM and paraffin and frozen sections and Micro-CT. There was high correlation between all parameters with statistical significance (p<0.05).Conclusions Significant differences in airway measurement were found among the different methods. The absolute measurements with CT IBM were closest to the histological results followed by Micro-CT, whereas CT FWHM demonstrated a distinct divergence from the other groups.Automated measurement techniques advance diagnosis of lung diseases. Pig bronchi wall size varies between Micro-CT, CT IBM, CT FWHM and histology. CT IBM is closest to histological results, followed by Micro-CT. CT FWHM differs highly from all other groups. https://bit.ly/3iRXSrv